Battery charger



Ju1y18,1944. E.. J. RUEB ETA.. 2,354,065

BATTERY CHARGER Filed April 15, 1943 2 sneetsfslwe'c,1,4

INVENTORS, Zf/JPZ/e, BY //VE 772//60/7.

July 18, 1944. E. J. Rui-:B ErAL BATTERY CHARGER Fiied AprilV 15, 194:5 2 sheets-sheet 2 v m, 4 l W a M, m Z H mem M ...al ab w 0 q i a, f7 .q my M a m wm MM w (r/J 6 o L W j@ 8 5 y, w, y w M w m w 2 4 j a 0 8 w Patented July 18, 1944 BATTERY CHARGER Earl I. Rueb and John E. Trulson, Kansas City, Mo.'

Application April 15, 1943, Serial No. 483,215

7 Claims.

This invention relates to improvements in storage battery charger system, and has particular reference to an improved battery charger suitable for rapid and safe charging. l

The principal object of the present invention is the provision of a storage battery charger having automatic control means within the primary circuit to vary the charging current.

Another object of the invention is the provision of a battery charger system which when started will automatically vary the charging rate and cut off when the battery is properly Charged without the use of any mechanical timing means.

A further object of the' invention 1s the provision of a storage battery charging system having an adjustable relay whereby the change of battery charging current may be varied to any degree or stage of the battery charge.

Other objects are simplicity and economy of construction, ease and safety of operation, and adaptability for use in charging storage batteries while positioned in the automobile.

Reference will now be had to the drawings wherein:

Fig. 1 is a plan view of a relay partly broken away and used in the system.

Fig. 2 is an end view partly in section of the relay shown in Fig. 1.

Fig. 3 is a sectional view taken on line III-III of Fig. 1.

Fig. 4 is a plan view of a variable resistance used in this system.

Fig. 5 is an end elevational view oi the variable resistance shown in Fig. 4.

Fig. 6 is a diagrammatic view showing the complete battery charging system.

Throughout the several viewslike reference characters refer to similar parts and thehu-v meral I8 designates a relay shown in detail in Figs. 1, 2, and 3 and comprising a base I2 of insulating material to which is attached by screw I4. a standard I6 which in turn carries van iron core or magnetic pole piece I8 in parallel relation with, but spaced apart vfrom the base I2. An insulating member 28 is positioned on core I8 to receive a heavy copper coil 22. 4About six coils of heavy wire has been found very satisfactory for coil 22. An armature 24 having a heavy supporting spring member 26 has a contact point 28 which is adapted to contact point 30 carried by rem silient bar 32 carried bybut insulated from standard I6 by insulators 34. The spring member 26 is secured to a bracket 38 pivotally mounted for adjustment by pin 38 on an L-shaped'bracket 40 l movement of the armature.

with an arcuate slot 42 through which the body of lock screw 44 extends to engage bracket 40 whereby the armature is adjusted relative tothe pole piece I8. This adjustment makes it possible to vary the resistance of the armature to the pull of the electromagnet. A stop 46 mounted in base member I2 serves to limit the outward provided with a binding post 48 and' the bar 32 has a binding post 50. It will be noted that the coil 22 terminates at its one end in a clamp I2 to receive the battery terminal |48 and at its other end in a clamp 56 to receive battery atrminal |46. A housing 60 mounted on base I2 serves to cover` the working parts of the relay, and isso constructed so as to prevent short circuiting of the electrical connectors. A starting coil 62 of relatively ne insulated wire is wound about coil 22. This starting coil is made of about two hundred turns relatively line wire which are disposed about core I8 so as to coact with coil 22 during the starting period.

Reference will now be had to the variable resistance thermostatic switch 64 comprising a base 66 to which is securely attached a vertical standard 68 by means of screw lll. Standard 68 is made of an electrical insulating material and carries two thermostatically operated switch members l2 and 14 in vertically spaced apart relation.

Switch member 72 comprises a bar I6 secured at its outer end to a bar 18 which is disposed at an acute'angle thereto so that the bars 18 and 'i8' engage opposite sides of standard 68 and are securely attached thereto by means of bolt 8U. These bars are adapted to carry an electric current and to expand and contract upon change of temperature. A relatively heavy coil 82 is wound about an insulating shield 84 encasing a portion of bar 16 and has one of its ends in contact with said bar and its other end connected in series in the primary circuit as hereinafter described. The extremity of bar 'I6 carries an adjustable switch point 86.

Switch member 14 is made in like manner to member 'l2 having two dlverging bars 88 and S6 contacting at their free ends and secured at their open ends on opposite sides of standard 68 by means of bolt 82. A resistance coil 84 of relative ly higher resistance than coil 82 is wound about bar 88 and insulated therefrom by an insulating boot 96, one end of this coil is fixed in contact with bar 88 while its other end is connected in the primary circuit. This switch member T4 secured to standard I6. Bracket 36 is provided 88 also carries an adjustable switch contact point $8 The armature is which is disposed in substantially axial alignment with switch point 86. When current is passed through coil 82, a bar 16 will be heated sufficiently to cause it to expand and move the switch point 86 so that it will contact the point 98 and close the switch whereby coils 82 and 94 will be connected in series as hereinafter described.

Reference will now be had to the battery charging system shown diagrammatically in Fig. 6. B designates the battery to be charged. The double pole switch is adapted to connect the A. C. current line wires |02 and |04 with the primary line wires |06 and |08 of the primary circuit of the system. A transformer ||0 having iron core |I2, primary coil ||4, and secondary coil ||6 having a plurality of taps ||8 adapted to be selectively connected in the secondary circuit by switch arm |20, is of the standard type. The rectifier |22 is shown as the bridge type but any other suitable type might be used.

Ammeter |24 and voltmeter |26 are also included in the battery charging circuit. A manually operable remote control double switch |28 is also included in the circuits. When the double pole switch |00 is closed and the hand operated double switch is closed, the current passes through live wire |06 to one side of the primary coil ||ll to wire |30 and to resistance coil 82. The current then passes to bar 16, bar 18 through wire |32 to switch member |34, to switch member |36 thence by wire |38 to the other live wire |08.

The secondary or battery charging circuit receives an induced current in coil ||6 when the switch arm is positioned on one of the taps ||8 and this current is conducted through wire |40 to the bridge rectifier |22. The other end of coil ||6 is connected through switch arm |20 and wire |42 to the other side of the rectifier. The direct current from the rectifier is conducted by wire |44 to charge battery B. The other side of the battery is connected by wire |46 to one end of resistance coil 22 of the relay. The other end of coil 22 is connected by wire |48 to the negative side of the rectifier. Starting coil 62 is joined to wire |48 by wire |50 and to switch member |52 by wire |54. The other switch member |56 is joined to wire |44 by conductor |58. The resilient bar 32 is connected by wire |60 to wire |32 and the armature is joined to wire |38 by means of wire |62. It will be noted that the ammeter |24 is in live wire |44 and that the voltmeter |26., is positioned across the battery charging lines.

The operation of the charger is as follows: The battery B is connected in the system, switch |00 is closed, then the operator presses the double switch |28 to the closed position, thus closing the primary circuit so that the alternating current from line |02 passes through wire |06, primary coil ||4, wire |30, resistance coil 82, bar 16, bar 18, wire |32, switch members |34 and |36, wire |38 to wire |08, switch |00 to live wire |04.

The induced current set up .in the secondary coil ||6 is connected by wire |40 to one side of the bridge rectifier and by wire |42 through closed switch arm |20 to the other side of coil |6. To vary the current in the charging circuit the switch arm may be set on any one of the taps ||8, thus lengthening or shortening the effective length of the coil. The direct current from the positive side of the rectifier passes through wire |44 to the battery B for charging and the other battery terminal is connected through wire |46, coil 22, and wire |48 to the negative side of the rectifier.

Current is also supplied to starting coil 62 when switch members |56 and |52 are closed through wire |54, coil 62, wire |50, wire |48, rectier |22, wire |44 and wire |58. The current in coil 62 and coil 22 is passing about core |8 in the same direction thus combining to increase the magnetic field in the core to operate the armature 24 to close switch contacts 28 and 30. When this relay switch is closed the operator may release switches |28 so that the current flow will be as follows: The current from live wire |02 will pass through wire |05, primary coil ||4, wire |30, resistance coil 82, bar 16, bar 18, wire |32, Wire |60, arm 32, point 30, wire |08 to the other live wire |04.

The battery charging circuit will be as follows: The direct current from the rectifier will pass by wire |44 to the battery, then by wire |46 to coil 22, thence to the rectifier by Wire |48. The Starting coil will now be cut out and if the resistance of the battery is not too high there will be sufficient current flow through coil 22 to maintain the switch points 28 and 30 closed. If the battery resistance is too high then it may be necessary for the operator to again close the double switch |28 until such time that there will be sufficient magnetic force to hold the armature 24 in contact with pole piece i8. It is to be remembered that the resistance of the armature to the magnetic pull may be varied to suit the currents and coil windings.

The current through coil 22 will be sufficient to maintain armature 24 closed until the battery has reached a predetermined degree of charge. During this first charging stage of the battery the contact points 86 and 98 will be closed due to the heating of the bar 16 by the current passing through coil 82, however due to the resistance of coil 94 no current will pass by wire |08 to the live wire |04.

As the battery reaches the preliminary charging stage, which should be below the violent gassing point or the dangerous stage, then the armature 24 will be released and the switch points 28 and 30 will be opened. The low battery charging current will now be on since the current from the primary coil will need to pass by wire |30 to coil 82, to bar 16, point 86, point 98. bar 88, coll 94, wire |08 to the live wire |04.

The higher resistance coil 84 is nowin series with coil 82 so that the points 86 and 98 will remain in contact with the battery until the same becomes properly charged regardless of the time required. When the battery is fully charged the current flow to the resistance coil 94 drops thus permitting bar 88 to cool sutllciently to open points 86 and 88 thus cutting olf the current to the system.

It is quite apparent that the battery charging rate might be varied so :1s '.-o have more thanl two stages by simply duplicating the relay and resistance coils just described, however the disclosure of the drawings and specification are sufficient to make clear the possibility of making as many stages as might be desired.

Many changes might be made in the construction of various elements of this system, furthermore, many modifications in the general arrangements of the parts might be made without depart. ing from the spirit of the invention and the scope of the appended claims.

What we claim as new and desire to cover by Letters Patent is:

l. A battery charger comprising a primary circuit. a secondary circuit adapted i'or connection with the terminals of the battery to be charged, means to vary the primary circuit whereby the battery charging rate is varied, said means including a thermostatic switch controlled by the secondary circuit as the battery is charged to a partial predetermined degree.

2. A battery charging system comprising a primary alternating circuit, a secondary circuit including a rectifier adapted to be connected with the terminals of the battery to be charged, means to vary the flow of current in said primary circuit whereby the battery charging rate is varied, said means including a thermostatic switch controlled by the secondary circuit as the battery is charged to a predetermined degree.

' 3. A battery charging system comprising a primary alternating circuit, a secondary circuit including a rectifier adapted to be connected with the terminals of the battery to be charged, means to vary the ilow of current in said primary circuit whereby the battery charging rate is varied,

-said means including a resistance operated by a thermostatic switch controlled by the secondary circuit as the battery is charged to a predetermined degree.

4. A battery charging system comprising a transformer having a plurality 'of taps, a rectiiier, a relay, a charging circuit, adapted to be connected with the terminals of a battery to be charged and including said rectifier, relay, and a switch member cooperating with said taps, and a primary circuit including a thermostatic switch controlled by said relay in said charging circuit whereby the charging current to said battery is varied.

5. A battery charging system comprising a transformer, a rectifier, a relay, a charging circuit adapted to be connected with the terminals of the battery to be charged and including said rectiiier, relay and the secondary coil of said transformer, a primary circuit including a source ot alternating current, the primary coil of said transformer and a variable resistance thermostatic switch controlled by vsaid relay until the battery has been charged to a predetermined degree and adapted to be automatically opened when the battery is fully charged.

6. A battery charging system comprising a transformer. a rectiiler, a relay, a charging circuit adapted to be connected with the terminalsl of the battery to be charged and including said rectiiier, relayand the secondary coil of said transformer, a primary circuit including a source of alternating current, the primary coil of said transformer and a variable resistance thermostatic switch connected through said relay until the battery has been charged to a predetermined partial degree and then connected through all the resistance of said yariable resistance directly to the current supply line whereby when the battery is fully charged said switch will open to cut oiI the current supply to the primary coll.

7. A battery charging system comprising a primary circuit. a charging circuit adapted forfconnection with the terminal of a battery to be charged and having means to vary the charging rate, said means including a pair of thermostatic switch members, and a relay having contact points adapted to short-circuit one of said switch members from the primary circuit until said battery has been partially charged and then to separate to permit the ilow of currentthrough both of said thermostatic switch members whereby the battery charging current in thev secondary circuit will be reduced until the battery is' completely charged and will then be automati-l cally cut oit.

. EARL J. RUEB.

JOHN E. TRULSON. 

